Display screen or portion thereof with transitional graphical user interface



FIG. 1 is a front view of a display screen or portion thereof withtransitional graphical user interface showing a first image in asequence, showing my new design;

FIG. 2 is a front view showing a second image thereof;

FIG. 3 is a front view showing a third image thereof;

FIG. 4 is a front view showing a fourth image thereof; and,

FIG. 5 is a front view showing a fifth image thereof.

The outermost perimeter illustrated by a pair of dashed broken linesshow the display screen or portion thereof and forms no part of theclaimed design. The remaining dashed broken lines illustrating portionsof the transitional graphical user interface form no part of the claimeddesign.

The appearance of the transitional graphical user interface sequentiallytransitions between the images shown in FIGS. 1-5. The process or periodin which one image transitions to another image forms no part of theclaimed design.

CLAIM The ornamental design for a display screen or portion thereof withtransitional graphical user interface, as shown and described.